generally you do not reverse with a walking foot- it is made to go forward-
it is up to you if you want to do a continuous line or stop and starts- just take a few tiny stitches at the end of a line-bring bobbin thread to the top and clip to finish a quilting line-some people leave tails which they tie together-thread onto a hand needle and bury- but if you take a few stitches in place it locks them so you can clip close to the surface of the quilt